Press Release here in Japanese
The research group led by Professor Hiroshi Niki, Osaka City University Graduate School of Literature and Human Sciences demonstrated the basic structure around the Honmaru of Osaka Castle in the age of Hideyoshi Toyotomi, a feudal lord, through a detailed underground survey.
It is the first time that the existence of remains by the castle tower and the southern end of Tsumenomaru where excavation had not been taken place in the past and where drawings were the only clues, was physically verified.
This four-year survey was conducted at approximately 300 spots adopting a technique called “Method for Swedish weight sounding test”, originally used for ground surveys. This method makes possible to know the condition of underground stone walls and structures without digging up the ground, development of investigation and research are expected in places where excavation is difficult such as designated historical sites.